Posted
by
samzenpuson Monday January 14, 2013 @09:48AM
from the spare-room dept.

cylonlover writes "NASA has announced that it has awarded a $17.8 million contract to Bigelow Aerospace to provide the International Space Station with an inflatable module. Details of the award will be discussed by NASA Deputy Administrator Lori Garver and Bigelow Aerospace President Robert Bigelow at a press conference on January 16 at the Bigelow Aerospace facilities in North Las Vegas. However, based on previous talks, it's likely that the module in question could be the Bigelow Expandable Activity Module (BEAM)."

Fixing costs isn't stupidity - it's good business. NASA gets the technology for $17.8 million, per the contract. If the technology costs more than expected to develop, the extra cost probably falls on Bigelow rather than taxpayers. Meanwhile, NASA's management and researchers can focus on other things that may have less commercial application, so they won't be developed without government support.

One of NASA's goals is to ensure that space technology continues to advance. It's not required to do all the wor

I lack the ambition to actually verify this one, but my experience with government contracts is that the vast majority are fixed-cost, same as any normal business transaction. Those that aren't usually have some percentage of additional cost applied, so the company will be absorbing most of the cost of overruns. I've yet to personally see a contract that says the government pays 100% for all cost overruns, but I do assume they exist.

Keep in mind that for every event that makes it to the news as a scandal, t

In this case with Bigelow, yes it is a fixed price contract. Indeed I am wondering a bit about the contract authority because the amount NASA is paying for this module is so miniscule that I'm not even sure it is from appropriations funding. Hell, this amount of $17 million is usually enough to fund just the RFP (request for proposals) for a "paper study" for some future high end project of this scale.

If you want to see some projects to make you turn white, just look at the James Webb Telescope or the SLS

Another example? This is pretty much the only example. It's quite novel for a president and administration to be so wrong on most fronts to get this relatively right. One wonders what he could have done, if he had dropped the ideological blinders from the start.

The way I heard it, the TransHab (inflatable module) had some really serious enemies in Congress. That is, enemies to the tune that the NASA budget was written to explicitly forbid any money for TransHab development. So NASA sold what they had to Bigelow, since they were legally forbidden to do anything else with it. (Just checked Wikipedia, and there is at least some level of confirmation for this.)

Bigelow has 2 TransHab-based test articles in orbit. Last I heard, they were planning their own "Space Ho

From a tank of compressed air. (Seriously, how is this even a question?)

they'd better have a puncture repair kit too

Presumably they will, but the walls of a module of this type are pretty thick (think car tire, not party balloon), there's multiples layers, and additional micrometeorite and debris shielding on top of that.

This is 17 million for the study. More importantly, beam will NOT be 65 tonnes. Heck, we have nothing that can take it up since the days of the saturn V. It is a SMALL closet that will weigh under 7 tonnes.

How much return of investment is the world getting from the ISS? Is it even close to the cost of maintaining it? If they did find some huge payoff, what would the rest of the world do, if Russia sent three Russian up there to kick off all non-Russian? The same Russians who probably instigated the problems in Georgia and used that as an excuse to intervene. I am just curious since there must be a reason why they want to expand it. I believe there is only 7 years left so if it takes another 2 years to g

the expansion is nothing. It is a small closet. It is so that NASA can test things on it. What is interesting is that BA has had 2 coffin-sizes in orbits for a number of years. So, the fabric works. Now, time to test other parts.

This announcement [nasa.gov] seems to be pretty clear that the $18 million (give or take with some change) is for the module and not merely a study. Yeah, this is causing my head to scratch too. I would think this amount is just throat clearing for a typical NASA project that would provide a stack of power point presentations suggesting a module in the future, but I don't see anywhere in the announcement that this is for a study but rather for actual flying hardware.

NASA will likely select a launch vehicle down the road and fund it separately. Being the ISS, it's possible that they will split the module cost with international partners, and then fund the rocket from their budget. Or one of many other options. Bigelow doesn't have their own rocket program so it wouldn't make sense to roll the launch vehicle into the same invoice.

You have got to admit though that if this $18 million is for production space hardware, that is pretty damn cheap. You would be hard pressed to get an individual NASA spacesuit for that price. I would dare say that the cost of preparing meals for the astronauts is pretty close to that figure on an annual basis. Considering that the ISS cost well more than $100 billion to be put into the sky in the first place, this amount of money is merely a rounding error for most NASA projects. It would even be a rea

Actually, this will be a small module. Apparently, they are looking at sending it up in the extended trunk of a dragon. The trunk has a length of over 4 M (~15'), and something like 30 m^3 volume. As such, they might be able to send this up next year in one of the scheduled dragons.

I know what was said in the article. It was a HORRIBLE article.
But think about it. There are no launchers today that can launch more than 21 tonnes. Delta IV heavy is the largest going today.
And yet, they are claiming that it would be 65 tonnes within 2 years? The author in this article is messing up all sorts of facts.
What is really missing is, that this can NOT be assembled in space. These are single units, i.e. it must be launched as one unit. here you go. [nasaspaceflight.com]

I suspect its $18M for a *flyable* module delivered to the launch pad, not for actually getting it to the ISS. Which isn't too shabby for what's basically a big balloon and maybe some life support systems in the central column.

Lets wait and see what happens on Weds. However, I agree with you that it would appear to be so. And actually, I have seen multiple links that said that it was for studies on it, not for the hardware. But, I am sure that you have seen nasa space flight is now saying otherwise ( i saw it after I posted here).

If this does turn out to be the "list price" for a module like this, it will literally blow away the traditional aerospace companies like Boeing and Northrop-Grumman. I really don't know for certain, and as you have said... we will find out on Wednesday. I'm sure that some reporter will ask this very question.

If this turns into the price for a study, the amount seems to be much more typical. The thing is that Bigelow knows how to make this stuff so I fail to see what a study might actually accomplish....

In fact, this might destroy ASI's work on the cans. It always drove me up a wall that we removed competition on the module constructions. BUT, each one of those cans cost something like 200 million on up.

OTOH, if is 17 million for this small unit, it will be a major paradigm shift. The reason is that BEAM was SUPPOSED to include CBM or LIDS on each side. If they can do all of this for 17 million and all that is needed is to extend the metal core, and increase the size of the outer fabric, well, that means

I just saw a brief comment on another site (pure speculation on this point though) that suggested this Bigelow module might be able to fly as a secondary payload on one of the SpaceX CRS flights and to put this into the "trunk" of the Dragon. If Bigelow could pull *that* off, it would be even more remarkable. A two for one special is the kind of thing that would prove commercial spaceflight really means to save costs.

I know. I saw that. Basically, it requires the F9 V1.1 and extended trunk (I mentioned that on another post in parallel to this).
But that is only if BEAM is as small as was originally planned. What is cool about it, is that it could mean that this would go up within a year. That is ideal for everybody. The reason is that it gets Bigelow's manufacturing lines going. Likewise, it allows NASA to play with things and prove to the world that all is good. After all, think of how much NASA has done for SpaceX and

Sure there is. And you can in fact buy durable versions of most products if you're willing to pay 5-10x as much, because building something durable is a lot more expensive than building it cheap, especially since they don't benefit much from economies of scale because most people would rather buy a new $10 widget every year than a $50 widget that will last 10 years.

Make the balloon a 2-layered affair with a few feet of air space. Then you fill that space with thousands of small floating balloons whose interiors are slightly sticky. Meteorite hits. Small balloons immediately travel to where the air is leaking out, burst, and plug the hole with a bunch of goopy rubber until someone (or some robot) can go outside once a month or so and put on maintenance patches.

they've had an inflatable module on orbit for something like 4 years - it's pretty well proven, and much cheaper to put into orbit than fixed-side vehicles. (And as for the idea that something might pop it, if debris is going to poke a hole in a vehicle at *orbital speeds*, it's going to go through kevlar just as easy as it's going to go through the metal the existing space station components are made of.)

I don't doubt the science behind the concept, and your point about debris being able to puncture the exterior no matter what is a good one. I'm curious about the potential psychological impact of the module. Even if it's completely irrational (and the FA says non-rigid exteriors are better able to withstand a micrometeor), I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one.

Having said that, being able to more than double the size, and presumably living space, of the ISS would probably do a great deal of good psychologically. Not to mention the fact that people who choose to go on missions to the ISS must have a certain amount of crazy to begin with, so probably wont care in the same way an ordinary mortal such as myself would.

The next question of course is how to get it up there? It's about 10x more than the maximum payload of either the Dragon or Soyuz rockets...

Have you seen any of the videos sent back from the ISS? From what the videos show, that thing is basically a maze of tunnels. There are a few (tiny) "rooms" off to the side, the cupola being the most notable and most different. (and biggest?) What's the long-term psychological impact of living in a "warren", and how great would the benefit be of having some real rooms?

On earth 6 foot ceiling is not all that much different than a 20-foot ceiling, because you arent going to use much of that space above 6 feet. But in micro-gravity you any of the six walls becomes a floor, thereby allowing you to use the entire volume. Less claustophobic in that case.

As one who happens to be 6'4", I'll say that on Earth a 6 foot ceiling is very different from a 20 foot ceiling. I'm not normally claustrophobic, but every now and then I just like to have some space around me. Skylab was interesting, in that respect, including the open framework floors.

Never having been in microgravity I can't tell how I'd respond, if being in a space 6'x6'x tens of feet would be sufficient for me, when I'm capable of moving in any of those dimensions.

I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one.

Agreed, though my (irrational) reasoning regards putting a sealed, pressurized object into a vacuum. Can it be done? Of course! Would I feel just as nervous about being in a space suit? While I cannot say for certain, I do not think so. But for some reason, thinking about being inside a balloon that isn't human-shaped leaves me feeling a little uneasy.

People live in tents with little problem, and the walls of these modules are rather high tech no matter what. Plus, when you fill it up to something resembling sea level(14.7 psi), you're going to have a structure that's about as stiff as the thin aluminum walls of a solid structure. They're almost certainly stronger - we have much better tensile strength materials than flexural strength. A big tube of aluminum will end up flexing on it's own, probably more than the inflated module.

These people ride rockets tinto orbit at 17,000 mph and come back in something which burns itself up to save their skins, all dependent on incredibly precise control, and you think they would waste any brain power to worry about the module popping from decompression?

Astronauts are probably the most anal-lytic of all adventurers, calculating everything to a fare-thee-well, practicing their missions for years in swim tanks to get every last detail down pat. The last thing they are going to do is become emoti

Even if it's completely irrational (and the FA says non-rigid exteriors are better able to withstand a micrometeor), I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one.

And? Sounds like the appropriate choice would be to get over your belief than to compromise your safety.

The next question of course is how to get it up there? It's about 10x more than the maximum payload of either the Dragon or Soyuz rockets...

Psychology revolves around what you see and feel. In this case, an astronaut floating into a Bigelow module attached to the ISS will be feeling an outer skin that feels exactly as rigid as the walls of the rest of the station. The material the module is made of is so strong and so thick and held in place so rigidly by air pressure that it feels as strong as steel to the touch. We know this because of inflated test modules on Earth. Inflate it to an equivalent pressure to what it will be on orbit, and th

ISS modules are protected by aluminium shields. The meteorite will hit this shield, punch through it but disintegrate in the process so it won't penetrate the module wall. They could flat-pack a set of shields alongside the inflatable module for launch.

The analogy to flat-pack furniture is spot on with what is happening here. This isn't just something that you "add water and watch it grow", it will be taking some assembly once the whole things is put up into orbit and in fact a sort of "flat-pack" system simply to squeeze everything into the payload faring. The main advantage of this style of module is that it ultimately has a whole bunch more volume, so station design can be more compact rather than having everything much more spread out.... as is the

This structure is more resistant to micrometeorite impacts than the other ISS modules. The penetrate less and are made of well known materials. These are fabrics designed for their rip resistance, because of that they are used in ropes, rigging for ships and gunshot/stab resistant vests.

One of these units has already been in space for years for testing purposes.

If you're thinking about the fragility of flexible walls, Wikipedia says [wikipedia.org]:

Bigelow Aerospace anticipates that its inflatable modules will be more durable than rigid modules.[13] This is partially due to the company's use of several layers of vectran, a material twice as strong as kevlar, and also because, in theory, flexible walls should be able to sustain micrometeoroid impacts better than rigid walls. In ground-based testing, micrometeoroids capable of puncturing standard ISS module materials penetrated only about half-way through the Bigelow skin. Operations director Mike Gold commented that Bigelow modules also wouldn't suffer from the same local shattering problems likely with metallic modules. This could provide as much as 24 hours to remedy punctures in comparison to the more serious results of standard ISS skin micrometeoroid damage.

I'm curious about pressure though. In the vacuum of space, if it's inflated to human-habitable pressures, won't the pressure difference between inside and outside put an enormous strain on the fabric?

Simple..... put the pressure gauge in a vacuum or use a pretty hard vacuum for comparison.

That is pretty much what would need to be done in a laboratory setting anyway.

For spacecraft, it really isn't that big of a deal compared to submarines, that need to be dealing with substantially larger pressure differences even if they go down just a couple hundred feet. Also, in a submarine they are worried about being crushed and need all sorts of structural support to keep that crushing from happening as opposed t

Given how cheaply most gauges are built, I'd simply say 'put the gauge markings assuming that the outside is at 14.7 PSI, sea level'.

But them being relative makes sense. You'd fill your vehicle up in Denver(mile high city) with a little less absolute pressure than in Florida, but that wouldn't matter much as there would be less air pressure trying to collapse them.

Also, if a rubber tire can withstand 90+ PSI*, I have no problems believing that an advanced hybrid using fibers tougher than kevlar can hold 14

I've seen bicycle tires that have 90+ PSI with no problem and I have some automobile on my car (admittedly non-standard) that have a normal pressure rating of 70 PSI that were even able to maintain that pressure with "foreign objects" inside of the tire for a prolonged period of time (long enough to get it repaired without even changing the tire and just "filling up" the tire with air before driving a dozen miles to the tire store).

Mm, but a tyre has 15 PSI (1 standard atmosphere) on the outside to counteract the 35 PSI on the inside.

This'll have 15 PSI on the inside, close to zero on the outside.

Accepting your numbers as valid (they aren't - the 35 psi in your tires is relative to atmospheric pressure, not absolute), that means a pressure differential on this module of 15 psi, as opposed to the 20 psi pressure differential on the tire.

Do you see a lot of tires exploding due to the pressure differential where you live?

I was looking around, it turns out that the inflatables produced by Bigelow have a 15 cm thick skin, and while I'm not finding any source, I seem to remember them inflating one up to 50+ PSI on the ground as part of some test and not having a problem.

But I guess (can anyone confirm) that the strain on the skin is proportional to internal pressure minus external pressure

Yes, strain and load are proportional to the pressure (force = pressure * area). The difficulty comes in due to the area being proportional to the square of the radius. This is why tires can handle 35-65 psi and scuba tanks are able to hold 3000 psi while commercial aircraft can be damaged by the relatively small (~8-9psi) cabin pressures. Aloha Airlines Flight 243 is one example and there are several more [wikipedia.org] here. [wikipedia.org]

The loads the skin of these Bigelow Aerospace modules must carry are very large and it isn't a

You're right, total pressure depends on the surface area, but when it comes to containing gas pressure, size matters less than you think.

You could make an aircraft that could hold the pressure of a scuba tank; but it'd be too heavy. A scuba tank is a LOT heavier for the surface area than a plane, and a plane needs to withstand many different stresses than the tank.

If you're making a tank, small or large the gauge of steel needed for the pressure remains about the same for the given pressure. Larger tanks

The situation is not quite as bad as you present, because we don't actualy care about the axial loads, we care about the skin stresses. Yes, pressure increases linearly with the amount of surface area (i.e. with the square of linear dimension), but the stress we care about is distributed along the skin cross section, which is directly proportional to the linear dimension.

For example lets think of "ring" of wall that makes up the middle of a cylindrical chamber. Air pressure is exerting a radial force outw

That's all true and makes for a good explanation of basic pressure vessel sizing. I was just trying to point out how much energy is being contained by structures like this. Most of the other posts seemed to dismiss the issue simply because the pressure isn't high.

At least I didn't go the inflammatory science "journalism" route and state that a fully inflated BA2100 is the equivalent of ~50kg of TNT!!!!!

From Wiki.
"The atmosphere on board the ISS is similar to the Earth's.Normal air pressure on the ISS is 101.3 kPa (14.7 psi);[139] the same as at sea level on Earth."
http://en.wikipedia.org/wiki/International_Space_Station [wikipedia.org]
Should be fine. Not too sure if would be ok 5-10m below sea; but it would really have gone wrong before that. So they may not build in any crushing force resistance at all.

I'm curious about pressure though. In the vacuum of space, if it's inflated to human-habitable pressures, won't the pressure difference between inside and outside put an enormous strain on the fabric?

Note that the Genesis testbeds have been in orbit for years with no problems.

Admittedly, Genesis was only inflated to 10 psi or so, and the ISS is pressurized to 14.7psi. But 14.7 psi is, presumably, well within the design specs of the module, since it was originally designed to handle a standard atmosphere

As others said, the difference between earth pressure and space pressure really isn't that great. 15 PSI differential is about the same as your car tires, and there are inflatable boats in current use that sustain even more. Pressurized diving suits regularly sustain pressure many dozens of times greater than this.

To (likely mis)quote Futurama:"We're going deep under the ocean, being subjected to thousands of atmospheres of pressure!""How much can the ship handle?""Well given that it's a spaceship, anywhere

I think the problem is that some people (myself included) thought that the proper way to compare it is interior pressure / exterior pressure. But from the comments, it sounds like interior pressure - exterior pressure is the correct way.

Right. Think of it like forces on a wagon - if you have two people pulling the same amount in in opposite directions the net force is zero and nothing happens. If one of them pulls with 1lb more force the net force is now 1lb, and the wagon will move as though there were only a single 1lb force acting on it, the rest of the force cancels out whether its 2lb or 2000.

Pressure is almost exactly the same thing, except you're talking about force-per-area - matching pressure cancels out, leaving the difference

yeah that would be 28 psi absolute, or 14 psi gauge. Unless you were testing it about 30 ft under water, which would probably be a great idea for leak detection.

Which is one of the reasons why Bigelow Aerospace has one of the largest swimming pools in Las Vegas (and that is saying a whole lot by itself). They intend to do not only underwater testing of these modules (or at least the design) before it goes up, but even provide an opportunity for astronauts to get up close and used to servicing the vehicle here on the Earth in a "neutral buoyancy simulator" (using scuba tanks to simulate EVAs).

Not necessarily. Pressure itself is not relative, there's a very definite zero-point in hard vacuum. Most pressure gauges are relative, because most of the reasons we care about pressure likewise depend on pressure differentials. You can however purchase pressure gauges that measure absolute pressure, though they tend to be much more expensive and the applications are limited. One that springs to mind is maintaining breathing gas - humans need a certain partial pressure range of oxygen to survive. Too l

It could be a lot less though, decrease the oxygen ppm by half and it can be 7 PSI, the pressure is not so important as maintaining the oxygen PPM as far as humans are concerned.

See apollo 1 fire. In orbit a 4 psi ppO2 fire is just a 4 psi ppO2 fire, doesn't matter much. But on the ground they like to pump that dude up to 4 psi over ambient to test for leaks before launch, especially hatch leaks. So you traditionally end up in 20 psi ppO2 and the slightest spark and "woosh" which is pretty much a summary of how everyone got killed in Apollo 1. Now sea level air means you have a ppO2 regulator so you leak test by pumping up to 20 psi absolute, of which most of the extra pressure

Other way around, *double* the O2 ppm and you can lower the pressure by half, since the partial pressure of O2 will then remain the same. In fact with a pure O2 environment you could cut the pressure to 1/5 atm (3psi) while still maintaining sea-level O2 pressure. You could possibly drop it even lower, most people can readily adapt to a 1.5psi partial pressure (~ 6000m), and at least some can adapt to 1psi (~9000m ~= peak of Mount Everest, which has been climbed without extra O2). I don't know how well w

I've lived in Cusco, Peru (11,200 feet/3400 meters), and after a week or two adjusting it's quite comfortable if you're not doing strenuous labor. After a month riding a bicycle or carrying a heavy load is still a bit more difficult than at sea level, but not dramatically so. There is no real reason to maintain a space station at sea level atmospheric pressure, except that the launch pad and training centers are at sea level so astronauts are used to it. Move your facilities to the Ecuadorian Andes (whic

Nobody else mentioned vibration and oscillation? Not a huge problem if you're using as a passive warehouse but giant fans blowing life support air are going to make the thing kinda floppy all the time.

I think this would be an interesting science experiment, both the biology of "is a space sickness adjusted human vulnerable to wobbly walls" and the science experiment of repetitive strain failure modes of flex materials (the skin doesn't bend twice, once when made and once when inflated in space, it bends at

I think this would be an interesting science experiment, both the biology of "is a space sickness adjusted human vulnerable to wobbly walls" and the science experiment of repetitive strain failure modes of flex materials (the skin doesn't bend twice, once when made and once when inflated in space, it bends at say 1 Hz continuous while deployed if the structure wobbles.

As far as the repetitive strain failure goes, there have been two testbeds of the inflatable module in space for five or so years each, neither of which failed that way.

And given the pressure differential involved, I suspect that the walls would seem as rigid as steel - 15cm thick, supported by 14.7psi (yes, I'm mixing measurement systems shamelessly) internal pressure isn't going to allow much room for "wobbly walls"....

You mean the same way your car tires are all wobbly? Or a firmly inflated balloon? Bouncy castles and such are wobbly because they're inflated to low pressures - inflate them to two atmospheres and they'd be practically rigid. Add in the fact that the module material likely has *very* little stretch and you'll get minimal flex.

Say your module has a 20ft diameter ~= 600 square feet cross section. Multiply that by 15psi and you get 1.3 million pounds of force keeping the opposite ends apart. There's no w

Not much as this is proven technology that not only they but NASA was working on in the 60's. The simple fact is at orbital velocities, there is nothing thats really going to stop anything nasty from going through the sides of something, you have little further to look than some of the damage done to the shuttles and Mir by space debris.

It isn't even recycling the TransHab concept. Simply put, it **IS** the TransHab concept, just rebranded. Robert Bigelow saw the TransHab technology languishing and being neglected with no chance to actually fly into space in spite of a module actually built and crated up ready to fly on the Space Shuttle. After talking to a bunch of folks at NASA, hiring his own engineers to take a look at the technology and be able to understand the engineering drawings for a few minor tweaks and improvements, he spend

You are getting far too conspiratorial here. No, it wasn't Robert Bigelow who "engineered" the defeat of TransHab from NASA appropriation bills. It was mainly a bunch of members of congress that wanted to simply kill the International Space Station altogether and were trying one little piece at a time, where the TransHab was seen as a ripe target because it was so different from the other modules.

Yes, your speculation is completely misplaced. As you've pointed out, this is something that happened over a